package com.juhui.gateway.filter;

import com.juhui.gateway.utils.WebFluxUtils;
import org.springframework.cloud.gateway.filter.GatewayFilterChain;
import org.springframework.cloud.gateway.filter.GlobalFilter;
import org.springframework.cloud.gateway.support.ServerWebExchangeUtils;
import org.springframework.core.Ordered;
import org.springframework.stereotype.Component;
import org.springframework.web.server.ServerWebExchange;
import reactor.core.publisher.Mono;

/**
 * 全局缓存获取body请求数据（解决流不能重复读取问题）
 *
 * @author melorogee
 */
@Component
public class GlobalCacheRequestFilter implements GlobalFilter, Ordered {

	@Override
	public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
		// 只缓存json类型请求
		if (!WebFluxUtils.isJsonRequest(exchange)) {
			return chain.filter(exchange);
		}
		return ServerWebExchangeUtils.cacheRequestBody(exchange, (serverHttpRequest) -> {
			if (serverHttpRequest == exchange.getRequest()) {
				return chain.filter(exchange);
			}
			return chain.filter(exchange.mutate().request(serverHttpRequest).build());
		});
	}

	@Override
	public int getOrder() {
		return Ordered.HIGHEST_PRECEDENCE + 1;
	}
}
